top study-index prior next ------------------------------------------------------------------------ ABCA SYNERGY: CHAOS / ORDER. ------------------------------------------------------------------------ ABCAA INFORMATION AND ORDER 1 ------------------------------------------------------------------------ This chapter requires some familiarity with the rudiments of physics and mathematics. It may be skipped by readers lacking this familiarity on condition, however, to accept: 1.the physical foundations of informatics as granted and 2.a loose definition of the concept of order. In the physics, the customary way to express the probability of a given heat distribution is the ENTROPY E defined by the BOLTZMANN expression (1ada.1): E = k ln(S) where k is the Boltzmanns gas constant and S is the number of microscopis states in which the macroscopis state E may be realized. The concept of entropy may be generalised by extending the expression over all forms of energy. Setting in the generalized expression k = 1/ln(2) we get: (1ada.2): E = ln(S) / ln(2) = log2(S) (where log2 means log base 2). 1ada.2 allows to express the entropy of the system as the number of digits of a binary string capable to address all possible system's states. Each digit of this string determines a degree of freedom of the system. Replacing entropy E with information I we may say that the complete set of system's states may be addressed with help of I binary bits: (1ada.3): I = log2(S) 1ada.2 and 1ada.3 express the analogy between the entropy and the information. @ The second law of thermodynamics, the "LAW OF ENTROPY" which may be generalised over all practical energetic systems states that any change of the system state increases its entropy. In the limit, for the purely theoretical reversible system, the entropy stays constant. It never decreases. Analogically, as result of a communication some of the I bits necessary to describe the S possible system states may get corrupted in which case the amount of useful information contained in I decreases. For each corrupted bit half of the possible system states S is excluded from the information I. This is the customary way of representing the analogy between entropy and information: information and entropy are isomorphic qualities differing in sign. ABCAA INFORMATION AND ORDER 2 Another way of presenting the analogy, which we find more appropriate for the present study is to consider not the information, but the information carrier as analogous and say that for each corrupted bit a new must be added in order to describe all S possible states of the system. In this context the analogy becomes strictly isomorphic and we may refer to I as to the ENTROPY OF INFORMATION, or shortly ENTROPY, when no misuderstanding about the nature of the involved system is possible. Entropy may be considered as the measure of disorder and its inverse as measure of order. Based upon the notion of entropy we define the ORDER of an information system: (1ada.4): O = I1 / I where I is systems entropy in a given situation and I1 = log2(S) is the minimum possible entropy of the system. Consequently, the highest possible order is 1. When entropy increases order decreases. Its value range is between 1 and 0. After introduction of the concept of order the law of entropy extended over information systems may be called LAW OF DECREASING ORDER and formulated: any spontaneous change of a system decreases its order. In the limit case of an ideal "reversible system", the order stays constant. It never increases. With respect to entropy and order INFORMATICS is analogous to physics. By virtue of this analogy we shall consider INFORMATICS as a natural domaine which may be investigated, ordered and processed with help of rigorous scientific methods.